Circuit breaker



June 17, 1952 J JACKSON 2,601,147

CIRCUIT BREAKER Filed Oct. 16, 1944 4 Sheets-Sheet l INVENTOR. Jbi/z 6. Jaw/50.

J- G. JACKSON CIRCUIT BREAKER June 17, 1952 4 Sheets-Sheet 2 Filed Oct; 16, 1944 1 v N W M fl/m 4 n June 17, 1952 J, JACKSON 2,601,147

CIRCUIT BREAKER Filed Oct. 16, 1944 4 Sheets-Sheet 3 l 44 l z/ June 17, 1952 J JACKSON 2,601,147

CIRCUIT BREAKER Filed Oct. 16, 1944 4 Sheets-Sheet 4 IN VEN TOR.

Patented June 17, 1952 CIRCUIT BREAKER John G. Jackson, Detroit, Mich., assignor to Square B Company, Detroit, Mich., a corporahan Mi h a application Qct obcr 16, 1944, Serial No. 558,822 8013 131 5. (01. 175-308) This invention relates to electric circuit breaker mountings and moreparticularlyto a circui br ker th'ciih hrb t o the ready ad 'tion of supplemental artist breakers'and oir its, as desired, in an 'eiist'ing" assemblage In the use of automatic lectric circuit br'eakers or circuit wiring'protection, it often happens that aiter an installation is inadit'is desired to provide for additional circuits and protection therefor. If an attempt is niadeto anticipate this iuture need in theinltial i 'tall'ati'on, it in eltcs ex nd t res Whith h greater th h se in tiall h e ed a "m ht'r be needed.-

the ot r hand, iti undesirable to add to the installa ion with an additional enclosure and separate breaker" mounting with its a tendan in reased Qt ah l d l j' t atkm 4 t m The..- hhie t o th pr sent inv nt is to roh s an lec r v c r uit, brain in which the numbe Q tircui theater a b 'n hir'cuits may be selected according to need at the tirne 9 in tall i a in. which P' h Oh i m d for easy addition oi supplemental circuit mesa he and r n h h mises fu ure use. h

In con tion w h i p t qi s th s it is a furthe t hs Obj t ti h i v h o p ov de for h ready ih e' lhck h o t el m a rcu ake s w h the txi "the t bre ker mount t set r t a l trical connection facilitating the circuit breaker li ieh i Ot er b ts an eat res of h ihvehti wi he readi a pa ent t t s s led 1 theh i em. t e s tti ttt h and a s ed drawillutratinsi i'r a httitrred em dim nts in whi h I I v I Fi ht- 1 s h hrhh eleva ihh v w of he thless hit it hr t t accordin Q t ete t'ht ih th ith- Figure g is a front elevational view of he evice unsure l h lh c i t ttht v d- Fi ure 3 is a, setticn it' eh th l nt TI ofs'i u eh- Fi ure is a se -tithe; vi w 9 3 t l WTW ofl' igure 2 Fi ure 5 is. a se tiszhel ew ihtqe h the 9 the sup leme ta circui hrt iitt t t t h t Bt eral ih V -V Of Fi ht"? i r i V M Figure 6 is. a de aile s etiehal View en t e l e vITvI of igure showin he shhtht l' the connection.

Figure 7 is a sectional view through one of the breaker elements of the initial lgreaker device on the general line VII-:V i Figu e 2- Figure 8 is a partial perspective view of a supplemental breaker mounting.

The circuit breaker assemblage, as Specifically illustrated in the drawing, comprises an outer enclosing box I havin an openable cover 2 through which project the operating handles 3 of the individual circuit breaker mechanism. Upon the back wall'of the box I is mounteda bracket i having frontwardly projecting legs 5, B and 7 received within slots in i 45 Of the main circuit breaker element to support and guide the same. The leg 6 is providedwith a circular threaded portion 8 more particularly shown in Figures 2 and 3 in which is threaded an adjusting screw 9 for holding the main circuit breaker element in its adjufi ltlil position within the box and relative to the front cover.

The main circuit breaker element comprises an insulating base I I within which are disposed four individual electric circuit breaker mechanisrns with the'vertically aligned mec ani m of mmon polarity and utilizing common contact plates 12 on which are disposed stationary QQ-ntact IS, the plates I2 being disposed adjacent the mid portion of the breaker unit and extending through the oppositesides thereof as straps it which are return bent into U form as shown in Figure 3 to form terminal connectors. The opposite legs of the U-shaped connectors [4 are connected by plates ['5 in which are threaded the studs 16. The space I! between the bight of the U -shaped connector and the bottom of the stud l6 serves for the attachment of line conductors which are clamped in position by'the tightening of the stud. The opposite side Walls of the. U- shaped connector f orwardly of the plate i5 serve for the reception of the line clips on the supplemental breaker units, as will be hereinafter'explained.

The opposite side walls of the base H are provided with dovetails an the opposite side walls of the supplemental" breaker 'units' [9 are provided with'cornplrnritary'dovetail slots 2| which receive the rrie to nount" the 'supplementa -v units either right or left hand relation. studs 3; are provided which' extend through half slots the side walls of the main base H and of'the supplementary unit [Band which thread into the"'dovetails I8 and'serve to prevent accidental removal of the supplemental units once they have'be'e'n installed; The supplemental units have, at one end, branch terminal connectors 23 carrying wire attaching means 2land at theifopposite' ends have line terminal connectors 25fcarridng clips 26 When the sup.-

plemental units are mounted upon the sides of the main initial breaker device by engagement of the dovetail slots in the units with the dovetails on the side walls of the main initial units, the insertion of the supplementary units l9 into their attached position will place the clips 26 within the U-shaped connector M with the opposite arms of the clip engaging the interior opposed surfaces of the legs of the connector as shown in Figures 2 and 3. When so mounted, the supplemental units are mechanically supported upon the initial breaker unit and have their line terminals electrically connected to the line terminals of the main unit.

While the particular circuit breaker mechanism utilized in the main and supplementary units forms no part of the present invention, these have been illustrated and will be briefly explained to effect a complete disclosure of an operative device. The supplementary unit, as illustrated in Figure 5, comprises a generally cupshaped base 21 in which the connectors 23 and 25 are supported into slots in the opposite side walls of the base. The connector 25 is maintained in place through the stud 28 connecting clip 26 to the connector 25 and also by the insulating plate 29 also received in slots in the base and maintained in position by the cover formed by the thin insulating sheet 3| and metallic plate 32, the cover and base being sealed by means of rivets 33. Upon the connector 25 is mounted the stationary contact 34 and cooperating therewith is a movable contact 35 mounted upon a switching blade 36. A formed insulating plate 3'! encloses an arc chamber about the cooperating contacts and has a slot 38 through which blade 35 extends. Guided in the opposite side walls of the base is a reciprocable member 39 having a slot 4| in which the blade 36 is disposed and the blade has an upper notch 42 engaging the member 39 as a pivotal support. A compression spring 43 is provided between the back wall of the base and the blade 36 and biases the blade forwardly and for rotation about its pivotal engagement with the rectilinearly movable member 39. An operating handle 44 pivots at 45 in the opposite side walls of the base and has a cam surface 46 engageable with the forward surface of the rectilinearly movable member 39 as the handle is rotated to cause backward movement of the member to effect manual off and reset operations of the breaker.

The connector 23 is guided in slots in op posite side walls of the base and is maintained in its interior position by terminal stud 24 and an adjusting stud 41. The terminal connector 23 has a pressed out portion 48 at the forward portion of which is mounted a bimetallic element 49 whose free end is electrically connected to the blade 36 by a flexible lead 5i. Upon the bimetallic element 49 is mounted a spring element 52 having a latching toe 53 engaged by the latching end of the switching blade 36. A U-shaped magnetic yoke 54 surrounds the bimetallic element 49 and a rotatable armature 55 is provided pivoted in the opposite side walls of the base on trunnions 56 and biased away from the yoke 54 by the end 51 of spring 52. A light spring element indicated at 58 biases the handle 44 to a definite on position so that it will indicate on an automatic trip.

The circuit breaker unit in Figure 5 is shown in the contacts engaged position. To manually move the contacts off to the off position, the handle 44 is rotated in a clockwise direction whereupon cam surface 46 will move the rec tilinearly movable member 39 toward the back of the base and the contact 35 will be similarly moved with the blade 36 pivoting about its latching engagement with the toe 53. Reverse or counterclockwise movement of the handle will thereafter effect return movement of the contacts to the engaged position under the action of spring 43. Upon current overload, the blade 53 will be unlatched for pivotal movement about its engagement with rectilinearly movable men.- ber 39. This may be effected either through flexing of the bimetallic element 49 due to heating or by the movement of the armature or by a combination of these actions. In the bimetallic trip, the element 49 becomes heated and flexes in a clockwise direction, moving the toe 53 out of latching engagement with the blade 36 to permit the aforesaid rotation of the blade in a clockwise direction to disengage the contact In the magnetic action, if the current overload is of sufficient value, the armature 55 will be attracted by the yoke 54 and will move the toe 53 relative to the bimetallic element 49 to eilect unlatching of the blade 35 and its consequent rotation to automatic tripped position. To again reset the breaker after an automatic operation, the handle 44 is rotated in a clockwise direction to press the member 39 toward the back of the base whereupon the blade 36 will engage the base adjacent its contact carrying end and will thereafter be rotated in a counterclockwise direction into relatching engagement with the toe 53. turn of the handle thereafter into on position will again effect engagement of the contacts.

The structure of the main breaker poles shown in Figure '7 is generally similar in construction and operation to that of the supplementary units of Figure 5. Centrally of the base ll are mounted the connectors I2 carrying stationary contacts [3, and extending in opposite directions toward the ends of the main original unit are switching blades 59 carrying movable contacts 6| cooperating with the stationary contacts [3. Rectilinearly movable members 62 are guided in the base and have slots 63 receiving the blades 59 and the blades have forward notches 64 providing pivotal engagement with the rectilinearly movable men bers. Compression springs 65 bias the blades 59 forwardly and for rotation about their engage ment with the rectilinearly movable members 82. Handles 66 have cam surfaces 61 for effecting movement of the rectilinearly movable members. Branch terminal connectors 68 are mounted on the base and have wire attaching studs 69 threaded therein. The interior ends of the connectors have pressed out portions 'H upon which are mounted bimetallic elements 12. Adjusting studs 13 are provided for determining the calibration tripping point of the breakers. Upon the bimetallic elements 12 are mounted spring strips 14 having latching toes I5. U-shaped magnetic yokes 16 surround the bimetallic element and pivotal armatures 11 are positioned for attraction thereto. Plates l8 divide the arcing chamber from the breaker mechanisms and have slots 19 through which the blades 59 extend. Light spring elements 8| bias the handle to a definite on position. The operation of the breaker unit shown in Figure 7 will be believed to be readily apparent from the description of the operation of the supplemental breaker unit of Figure 5.

Upon the back wall of the box I is mounted an insulating block 82 in which are mounted D Lueterminal screws 83 for the reception of neutral wires. 1

While certain preferred embodiments, of. the invention have been specifically disclosed, it is understood that the invention is not limited thereto, as many variations will be readily apparent to those skilled in the art and the. invention is to be given its broadest possible; interpretation within the. terms. of the following claims.

What is claimed is:

1. In an automatic electric circuit breaker assemblage, a principal circuit breaker unit, a line terminal on said principal circuit breaker unit, means for mounting said principal circuit breaker unit, a supplemental circuit breaker unit directly mechanically mounted and supported on said principal circuit breaker unit, a line terminal on said supplemental circuit breaker unit, and means for interconnecting said line terminals on said principal and supplemental units, said interconnecting means comprising complementary U-shaped terminals on said principal and supplemental circuit breaker units which slidably engage under pressure to effect the electrical connection.

2. In an automatic electric circuit breaker assemblage, a principal breaker unit comprising a plurality of individual breaker mechanisms mounted within a common enclosure, means for mounting said principal unit, line terminals at the opposite sides of said principal unit and adjacent the mid-point thereof, individual supplemental circuit breaker units comprising individual enclosures and circuit breaker mechanisms therein mountedat the sides of said principal unit by slidably interlocking means on the cooperating side Walls of said principal unit and supplemental units, and means connecting the line terminals of said supplemental units to the line terminals of the main unit by the act of slidably interlocking the side walls of said main and supplemental units.

3. In an automatic electric circuit breaker assemblage, a principal breaker unit comprising a plurality of individual breaker mechanisms mounted within a common enclosure, means for mounting said principal unit, line terminals at the opposite sides of said principal unit and adjacent the mid-point thereof, individual supplemental circuit breaker units comprising indi vidual enclosures and circuit breaker mechanisms therein mounted at the sides of said principal unit by slidably interlocking means on the cooperating side walls of said principal unit and supplemental units, and means connecting the line terminals of said supplemental units to the line terminals of the principal unit by the act of slidably interlocking the side walls of said main and supplemental units, said connecting means comprising complementary members slidably engaging under tension to effect the electrical connection of the line terminals.

4. In an automatic electric circuit breaker assemblage, a principal breaker unit comprising a plurality of individual breaker mechanisms mounted within a common enclosure, means for mounting said principal unit, line terminals at the opposite sides of said principal unit and adjacent the midpoint thereof, individual supplemental circuit breaker units comprising individual enclosures and circuit breaker mechanisms therein mounted at the sides of said principal unit by slidably interlocking means on the cooperating side walls of said principal and ably interlocking means on the side walls of said principal and supplemental units, line terminals for said principal and supplemental units, and means electrically interconnecting said line terminals, said means comprising conducting connectors slidably engaged by the slidable interlocking of the supplemental units on the principal unit.

6. In an electric circuit breaker assemblage, an enclosing box, a principal circuit breaker unit mounted in said box and comprising an enclosure, a manual and automatic electric circuit breaker mechanism within the enclosure, supplemental circuit breaker units comprising enclosures and manual and automatic electric circuit breaker mechanisms Within the enclosures, said supplemental units being directly mechanically supported upon said principal unit by slidably interlocking means integrally formed on the side walls of the enclosures of said principal and supplemental units, and line connectors on said principal and supplemental circuit breaker units interconnecting by engagement as the supplemental units are slidably interlocked with the principal units.

'7. In an automatic electric circuit breaker assemblage, a principal circuit breaker unit comprising an enclosure containing at least one manually and automatically operable electric circuit breaker mechanism, means for mounting said principal circuit breaker unit, a line terminal on said principal circuit breaker unit, a supplemental circuit breaker unit directly mechanically mounted on said principal circuit breaker unit, said supplemental circuit breaker unit comprising an enclosure and a manually and automatically operable circuit breaker mechanism therein, a line terminal on said supplemental circuit breaker unit and means for interconnecting the line terminals on said principal and supplemental units, said last mentioned means comprising a pressure clip engagement facilitating the attachment and detaching of said supplemental unit.

8. In an electric circuit breaker assemblage, an enclosing box, a principal circuit breaker unit mounted in said box and comprising an enclosure within which is disposed at least one manually and automatically operable electric circuit breaker mechanism, supplemental circuit breaker units directly mechanically supported upon said principal circuit breaker unit, said supplemental units comprising enclosures and manually and automatically operable electric circuit breaker mechanisms therein, said supplemental units be ing supported on said principal unit by slidably interlocking means integrally formed on the side walls of the enclosures of said principal and supplemental units, line terminals for said principal 'and supplemental units, and means electrically interconnecting said line terminals, said last mentioned means slidably engaging as the supplemental units are interlocked with the principal unit.

JOHN G. JACKSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Date Number Number Name Date Meuer July 18, 1933 Williams Dec. 5, 1933 Sachs Oct. 3, 1939 Borkenstein Jan. 9, 1940 Anderson Dec. 24, 1940 Pokomy May 18, 1943 Bush Nov. 30, 1943 Johansson Mar. 20, 1945 Christensen Apr. 24, 1945 FOREIGN PATENTS Country Date Great Britain May 2, 1935 

